MM JTM45/100 PT

[trane34]

Hello all. Can someone please tell me how to wire up the MM JTM45/100 PT? It does not have the usual center tapped wiring that I am used to using. I've attached their wiring diagram.

[ToneMerc]

Here's two schemes of wiring the high side tapped dual secondaries. I used a Marstran 1203-80. This should transpose to the MM I think.

A=3-high (188)

B=2-low (168)

C=1-common (0)

D=4-common (0)

E=5-low (168)

F=6-high (188)

Bias- yes ground one side


TM

[Phil_S]

deleted, Tone Merc got there first with nice pictures

[trane34]

That's awesome. Thanks for the help guys!

[Roe]

45/100s typically used the 1204-43, not the 1203-80. That MM tranny is based on the latter, not the former, and therefore incorrect for most 45/100s (except the very, very first superleads and superbasses or the very last jtm45s)

[trane34]

45/100s typically used the 1204-43, not the 1203-80. That MM tranny is based on the latter, not the former, and therefore incorrect for most 45/100s (except the very, very first superleads and superbasses or the very last jtm45s)

Good to know. Thanks for the info. I'm glad I'm not using it for a exact clone. I just thought it would be a versatile PT and plan to use it for a variety of builds. The first I am trying is a JCM800 as I happen to have the parts laying around. The cool thing is that the universal mounting of this PT fits an weber 6a80 (twin chassis) that I had. I plan on using the PT later on for a bluesmaster build in a CE chassis.

[trane34]

Just on the off chance that someone happens to buy this PT. I first wired the output taps according to the Marstran diagrams but I ended up with the wrong voltages. Instead, after disconnecting any jumpers and metering the taps I found it was wired different from the MM schematic. Lesson learned to not always trust wiring diagrams. At least it was an easy fix as I could just change the leads.